Why aren't they just snapshotting and archiving the full git repo? Does `git bundle` add something over frequent ZFS backups?
https://git-scm.com/docs/gitfaq#_transfers
It doesn't tell you how to make a backup safely though.
On a personal scale, Syncthing and Btrfs snapshots work plenty good enough. It's as fast as the storage/network too.
Because it's at a personal scale, the only time I can corrupt a git repo is if I work on the same repo (and it's workdir) from more than one device in the time it takes for Syncthing to replicate the changes.
But even then it's not a big deal because git fsck is quick. And I have my snapshots, and the syncthing versioning, and git defaults to two weeks before pruning. And because of how git works, using hash to identify contents, files are not easily overwritten either.
In 10y I only had one git corruption (I ran a command on the same repo on a different machine via ssh, yielding a synctning conflict). Syncthing kept copies of the conflict file. One commit disappeared from the history but not from the database. It was easy to rebase the changes. I think I used git fsck to deleted the syncthing versioned files.
That said, there's another less known feature that bundles help out with when used with `git clone --bundle-uri` The client can specify a location to a bundle, or the server can send the client the bundle location in the clone results and the client can fetch the bundle, unpack it, and then update the delta via the git server, so it's a lot lighter weight on the server for cloning large repos, and a ton faster for the client for initial clones.
EDIT: you could also rsync from a .zfs snapshot directory if you have them enabled.
... is this really the way people "back up" git repos? I mean, it is git, so isn't there some way to mirror changes to the repo in another repo and just use ZFS / snapshots / backup software / etc to do that? It's a distributed version control system. Just make sure the version control information is ... distributed?